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                <ol class="chapter"><li class="chapter-item affix "><a href="../../index.html">Andrew's Blog</a></li><li class="chapter-item "><a href="../../posts/linux/linux.html"><strong aria-hidden="true">1.</strong> Linux</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/linux/install_linux.html"><strong aria-hidden="true">1.1.</strong> install linux</a></li><li class="chapter-item "><a href="../../posts/linux/bash_profile.html"><strong aria-hidden="true">1.2.</strong> bash profile</a></li><li class="chapter-item "><a href="../../posts/linux/command_list.html"><strong aria-hidden="true">1.3.</strong> command list</a></li><li class="chapter-item "><a href="../../posts/linux/git_guide.html"><strong aria-hidden="true">1.4.</strong> git guide</a></li><li class="chapter-item "><a href="../../posts/linux/tar.html"><strong aria-hidden="true">1.5.</strong> tar</a></li><li class="chapter-item "><a href="../../posts/Linux/git_cheatsheet.html"><strong aria-hidden="true">1.6.</strong> Git Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/Linux/bash_cheatsheet.html"><strong aria-hidden="true">1.7.</strong> Bash Cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/macos/mac.html"><strong aria-hidden="true">2.</strong> MacOS</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/macos/macos_profiles.html"><strong aria-hidden="true">2.1.</strong> macos profiles</a></li><li class="chapter-item "><a href="../../posts/macos/macos_pwn_env_setup.html"><strong aria-hidden="true">2.2.</strong> macos pwn env setup</a></li></ol></li><li class="chapter-item "><a href="../../posts/swift/swift.html"><strong aria-hidden="true">3.</strong> Swift</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/swift/learn_swift.html"><strong aria-hidden="true">3.1.</strong> learn swift basics</a></li><li class="chapter-item "><a href="../../posts/swift/swift_extensions.html"><strong aria-hidden="true">3.2.</strong> Swift extensions</a></li><li class="chapter-item "><a href="../../posts/swift/swiftui_extension.html"><strong aria-hidden="true">3.3.</strong> SwiftUI extensions</a></li><li class="chapter-item "><a href="../../posts/swift/install_swift.html"><strong aria-hidden="true">3.4.</strong> install swift</a></li><li class="chapter-item "><a href="../../posts/swift/task_planner.html"><strong aria-hidden="true">3.5.</strong> implment task panner app with SwiftUI</a></li><li class="chapter-item "><a href="../../posts/swift/swift_cheat_sheet.html"><strong aria-hidden="true">3.6.</strong> Swift Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/swift/yinci_url.html"><strong aria-hidden="true">3.7.</strong> Personal privacy protocol</a></li><li class="chapter-item "><a href="../../posts/swift/swift_regular_exressions.html"><strong aria-hidden="true">3.8.</strong> Swift regular exressions</a></li><li class="chapter-item "><a href="../../posts/ios/how_to_create_beautiful_ios_charts_in_swift.html"><strong aria-hidden="true">3.9.</strong> How to Create Beautiful iOS Charts in Swift</a></li><li class="chapter-item "><a href="../../posts/swift/swiftui_source_code.html"><strong aria-hidden="true">3.10.</strong> SwiftUI source code</a></li><li class="chapter-item "><a href="../../posts/swift/use_swift_fetch_iciba_api.html"><strong aria-hidden="true">3.11.</strong> use swift fetch iciba API</a></li></ol></li><li class="chapter-item "><a href="../../posts/ios/ios.html"><strong aria-hidden="true">4.</strong> iOS</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ios/cocaposd_setup_and_install_for_ios_project.html"><strong aria-hidden="true">4.1.</strong> cocaposd setup and install for ios project</a></li><li class="chapter-item "><a href="../../posts/ios/swiftui_show_gif_image.html"><strong aria-hidden="true">4.2.</strong> SwiftUI show gif image</a></li><li class="chapter-item "><a href="../../posts/ios/implement_task_planner_app.html"><strong aria-hidden="true">4.3.</strong> implement Task planner App</a></li></ol></li><li class="chapter-item "><a href="../../posts/objective_c/objective_c.html"><strong aria-hidden="true">5.</strong> Objective-C</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/objective_c/objective_c_cheat_sheet.html"><strong aria-hidden="true">5.1.</strong> Objective-C Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/objective_c/objective_c_for_absolute_beginners_read_note.html"><strong aria-hidden="true">5.2.</strong> Objective-C Note</a></li></ol></li><li class="chapter-item "><a href="../../posts/dart/dart.html"><strong aria-hidden="true">6.</strong> Dart</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/dart/flutter.html"><strong aria-hidden="true">6.1.</strong> Flutter Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/dart/dart_cheat_sheet.html"><strong aria-hidden="true">6.2.</strong> Dart Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/flutter/flutter_dev_test.html"><strong aria-hidden="true">6.3.</strong> Flutter dev test</a></li></ol></li><li class="chapter-item "><a href="../../posts/rust/rust.html"><strong aria-hidden="true">7.</strong> Rust</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/rust/offline_use_rust.html"><strong aria-hidden="true">7.1.</strong> Offline use rust</a></li><li class="chapter-item "><a href="../../posts/rust/rust_grammer.html"><strong aria-hidden="true">7.2.</strong> rust grammar</a></li><li class="chapter-item "><a href="../../posts/rust/pase_string_and_decimal_conversion.html"><strong aria-hidden="true">7.3.</strong> pase string and decimal conversion</a></li><li class="chapter-item "><a href="../../posts/rust/parse_types.html"><strong aria-hidden="true">7.4.</strong> rust types</a></li><li class="chapter-item "><a href="../../posts/rust/rust_life_cycle.html"><strong aria-hidden="true">7.5.</strong> Rust life cycle</a></li><li class="chapter-item "><a href="../../posts/rust/rust_generic.html"><strong aria-hidden="true">7.6.</strong> rust generics</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implment_matrix.html"><strong aria-hidden="true">7.7.</strong> Rust implement matrix</a></li><li class="chapter-item "><a href="../../posts/rust/rust_sort.html"><strong aria-hidden="true">7.8.</strong> Rust implement sort algorithms</a></li><li class="chapter-item "><a href="../../posts/rust/implement_aes_encryption.html"><strong aria-hidden="true">7.9.</strong> Rust implement AEC encryption and decryption</a></li><li class="chapter-item "><a href="../../posts/rust/implement_trie_data_structure.html"><strong aria-hidden="true">7.10.</strong> implement trie data structure</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implement_tree.html"><strong aria-hidden="true">7.11.</strong> implement tree data_structure</a></li><li class="chapter-item "><a href="../../posts/rust/list_dir.html"><strong aria-hidden="true">7.12.</strong> list dir</a></li><li class="chapter-item "><a href="../../posts/rust/fast_way_to_implment_object_trait.html"><strong aria-hidden="true">7.13.</strong> fast way to implment object trait</a></li><li class="chapter-item "><a href="../../posts/rust/compress_rust_binary_size.html"><strong aria-hidden="true">7.14.</strong> compress rust binary size</a></li><li class="chapter-item "><a href="../../posts/rust/implment_file_upload_backend.html"><strong aria-hidden="true">7.15.</strong> impliment file upload</a></li><li class="chapter-item "><a href="../../posts/rust/this_is_add_post_cli_implementation_in_rust.html"><strong aria-hidden="true">7.16.</strong> this is add_post cli implementation in rust</a></li><li class="chapter-item "><a href="../../posts/rust/use_rust_implment_a_copyclipbord_cli.html"><strong aria-hidden="true">7.17.</strong> Use rust implment a copyclipbord CLI</a></li><li class="chapter-item "><a href="../../posts/rust/sqlite_database_add_delete_update_show_in_rust.html"><strong aria-hidden="true">7.18.</strong> sqlite database add delete update show in rust</a></li><li class="chapter-item "><a href="../../posts/rust/implementing_tokio_joinhandle_for_wasm.html"><strong aria-hidden="true">7.19.</strong> Implementing tokio JoinHandle for wasm</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implement_a_crate_for_encode_and_decode_brainfuck_and_ook.html"><strong aria-hidden="true">7.20.</strong> rust implement a crate for encode and decode brainfuck and ook</a></li><li class="chapter-item "><a href="../../posts/rust/slint_builtin_elements.html"><strong aria-hidden="true">7.21.</strong> Slint Builtin Elements</a></li><li class="chapter-item "><a href="../../posts/rust/corporate_network_install_rust_on_windows.html"><strong aria-hidden="true">7.22.</strong> Corporate network install Rust on windows</a></li><li class="chapter-item "><a href="../../posts/rust/rust_binary_file_how_to_judge_static_link_or_dynamic_link_in_macos.html"><strong aria-hidden="true">7.23.</strong> rust binary file how to judge static link or dynamic link in Macos</a></li><li class="chapter-item "><a href="../../posts/rust/rust_binary_include_dir_and_get_contents.html"><strong aria-hidden="true">7.24.</strong> rust binary include dir and get contents</a></li><li class="chapter-item "><a href="../../posts/rust/how_to_create_yolov8_based_object_detection_web_service_using_python,_julia,_node.js,_javascript,_go_and_rust.html"><strong aria-hidden="true">7.25.</strong> How to create YOLOv8-based object detection web service using Python, Julia, Node.js, JavaScript, Go and Rust</a></li><li class="chapter-item "><a href="../../posts/rust/implment_builder_proc_macro_for_command_struct.html"><strong aria-hidden="true">7.26.</strong> implment Builder proc-macro for Command struct</a></li></ol></li><li class="chapter-item "><a href="../../posts/java/java.html"><strong aria-hidden="true">8.</strong> Java</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/java/java_grammar.html"><strong aria-hidden="true">8.1.</strong> java grammar and codewar</a></li><li class="chapter-item "><a href="../../posts/java/run_jar.html"><strong aria-hidden="true">8.2.</strong> java run .jar</a></li><li class="chapter-item "><a href="../../posts/java/java_pomxml_add_defaultgoal_to_build.html"><strong aria-hidden="true">8.3.</strong> Java pomxml add defaultGoal to build</a></li><li class="chapter-item "><a href="../../posts/java/java_set_mvn_mirror.html"><strong aria-hidden="true">8.4.</strong> Java set mvn mirror</a></li></ol></li><li class="chapter-item "><a href="../../posts/python/python.html"><strong aria-hidden="true">9.</strong> Python</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/python/convert_pesn.html"><strong aria-hidden="true">9.1.</strong> convert pesn</a></li><li class="chapter-item "><a href="../../posts/python/find_remove_dir.html"><strong aria-hidden="true">9.2.</strong> find and remove dir</a></li><li class="chapter-item "><a href="../../posts/python/timing_message.html"><strong aria-hidden="true">9.3.</strong> wechat send message</a></li><li class="chapter-item "><a href="../../posts/python/use_python_openpyxl_package_read_and_edit_excel_files.html"><strong aria-hidden="true">9.4.</strong> Use python openpyxl package read and edit excel files</a></li><li class="chapter-item "><a href="../../posts/python/sanctum_model_yaml.html"><strong aria-hidden="true">9.5.</strong> sanctum model yaml</a></li><li class="chapter-item "><a href="../../posts/python/how_to_detect_objects_on_images_using_the_yolov8_neural_network.html"><strong aria-hidden="true">9.6.</strong> How to detect objects on images using the YOLOv8 neural network</a></li><li class="chapter-item "><a href="../../posts/python/use_huggingface_model.html"><strong aria-hidden="true">9.7.</strong> use huggingface model</a></li></ol></li><li class="chapter-item "><a href="../../posts/go/go.html"><strong aria-hidden="true">10.</strong> Go</a></li><li class="chapter-item expanded "><a href="../../posts/javascript/js.html"><strong aria-hidden="true">11.</strong> Javascript</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/javascript/js_tutorial.html"><strong aria-hidden="true">11.1.</strong> js tutorial</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_map.html"><strong aria-hidden="true">11.2.</strong> ja map</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_math.html"><strong aria-hidden="true">11.3.</strong> js math</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_object.html"><strong aria-hidden="true">11.4.</strong> js object</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_set.html"><strong aria-hidden="true">11.5.</strong> js set</a></li><li class="chapter-item "><a href="../../posts/javascript/single_thread_and_asynchronous.html"><strong aria-hidden="true">11.6.</strong> single thread and asynchronous</a></li><li class="chapter-item "><a href="../../posts/javascript/this.html"><strong aria-hidden="true">11.7.</strong> js this</a></li><li class="chapter-item "><a href="../../posts/javascript/js_implment_aes.html"><strong aria-hidden="true">11.8.</strong> js implment aes</a></li><li class="chapter-item "><a href="../../posts/javascript/getting_started_with_ajax.html"><strong aria-hidden="true">11.9.</strong> getting started with ajax</a></li><li class="chapter-item "><a href="../../posts/javascript/BinarySearchTree.html"><strong aria-hidden="true">11.10.</strong> binary search tree</a></li><li class="chapter-item "><a href="../../posts/javascript/goole_zx.html"><strong aria-hidden="true">11.11.</strong> goole zx</a></li><li class="chapter-item expanded "><a href="../../posts/javascript/es6.html" class="active"><strong aria-hidden="true">11.12.</strong> es6</a></li></ol></li><li class="chapter-item "><a href="../../posts/ruby/ruby.html"><strong aria-hidden="true">12.</strong> Ruby</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ruby/rails_setup_env.html"><strong aria-hidden="true">12.1.</strong> ruby on rails setup environment</a></li><li class="chapter-item "><a href="../../posts/ruby/learn_ruby.html"><strong aria-hidden="true">12.2.</strong> learn ruby</a></li><li class="chapter-item "><a href="../../posts/ruby/ruby_note.html"><strong aria-hidden="true">12.3.</strong> Ruby Note</a></li><li class="chapter-item "><a href="../../posts/ruby/setup_ruby_for_ctf.html"><strong aria-hidden="true">12.4.</strong> Setup ruby for CTF</a></li></ol></li><li class="chapter-item "><a href="../../posts/react/react.html"><strong aria-hidden="true">13.</strong> React</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/react/react_life_cycle.html"><strong aria-hidden="true">13.1.</strong> react life cycle</a></li><li class="chapter-item "><a href="../../posts/react/react_router.html"><strong aria-hidden="true">13.2.</strong> react router</a></li><li class="chapter-item "><a href="../../posts/react/react_this.html"><strong aria-hidden="true">13.3.</strong> react this</a></li><li class="chapter-item "><a href="../../posts/react/react_interviw.html"><strong aria-hidden="true">13.4.</strong> react interview</a></li><li class="chapter-item "><a href="../../posts/react/important_react_interview.html"><strong aria-hidden="true">13.5.</strong> important react interview</a></li><li class="chapter-item "><a href="../../posts/react/react_quick_reference.html"><strong aria-hidden="true">13.6.</strong> react quick reference</a></li><li class="chapter-item "><a href="../../posts/react/redux_quick_reference.html"><strong aria-hidden="true">13.7.</strong> redux quick reference</a></li></ol></li><li class="chapter-item "><a href="../../posts/vue/vue.html"><strong aria-hidden="true">14.</strong> Vue</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/vue/vue_ajax.html"><strong aria-hidden="true">14.1.</strong> vue ajax</a></li></ol></li><li class="chapter-item "><a href="../../posts/angular/angular.html"><strong aria-hidden="true">15.</strong> Angular</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/angular/controller_communication.html"><strong aria-hidden="true">15.1.</strong> controller communication</a></li><li class="chapter-item "><a href="../../posts/angular/creating_custom_directives.html"><strong aria-hidden="true">15.2.</strong> creating custom directives</a></li><li class="chapter-item "><a href="../../posts/angular/directive_notes.html"><strong aria-hidden="true">15.3.</strong> directive notes</a></li><li class="chapter-item "><a href="../../posts/angular/directive_communication.html"><strong aria-hidden="true">15.4.</strong> directive communication</a></li><li class="chapter-item "><a href="../../posts/angular/post_params.html"><strong aria-hidden="true">15.5.</strong> post params</a></li><li class="chapter-item "><a href="../../posts/angular/read_json_angular.html"><strong aria-hidden="true">15.6.</strong> read json angular</a></li><li class="chapter-item "><a href="../../posts/angular/same_route_reload.html"><strong aria-hidden="true">15.7.</strong> same route reload</a></li></ol></li><li class="chapter-item "><a href="../../posts/css/css.html"><strong aria-hidden="true">16.</strong> Css</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/css/use_css_media.html"><strong aria-hidden="true">16.1.</strong> use css media</a></li></ol></li><li class="chapter-item "><a href="../../posts/php/php.html"><strong aria-hidden="true">17.</strong> Php</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/php/for_php_string_implment_some_extemtion_functions.html"><strong aria-hidden="true">17.1.</strong> for php string implment some extemtion functions</a></li><li class="chapter-item "><a href="../../posts/php/php_cheatsheet.html"><strong aria-hidden="true">17.2.</strong> PHP cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/windows/windows.html"><strong aria-hidden="true">18.</strong> Windows</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/windows/windows.html"><strong aria-hidden="true">18.1.</strong> Windows</a></li><li class="chapter-item "><a href="../../posts/windows/windows10_use_powershell_dedup_redundent_path.html"><strong aria-hidden="true">18.2.</strong> Windows10 use PowerShell dedup redundent PATH</a></li></ol></li><li class="chapter-item "><a href="../../posts/leetcode/leetcode.html"><strong aria-hidden="true">19.</strong> Leetcode</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/leetcode/rust_leetcode.html"><strong aria-hidden="true">19.1.</strong> rust leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_codewar.html"><strong aria-hidden="true">19.2.</strong> rust codewar</a></li><li class="chapter-item "><a href="../../posts/leetcode/swift_codewar.html"><strong aria-hidden="true">19.3.</strong> swift codewar</a></li><li class="chapter-item "><a href="../../posts/leetcode/js_leetcode.html"><strong aria-hidden="true">19.4.</strong> js leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/java_leetcode.html"><strong aria-hidden="true">19.5.</strong> java leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_huawei.html"><strong aria-hidden="true">19.6.</strong> huawei test</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_utils.html"><strong aria-hidden="true">19.7.</strong> rust common functions</a></li><li class="chapter-item "><a href="../../posts/leetcode/olympiad_training.html"><strong aria-hidden="true">19.8.</strong> Computer olympiad training</a></li></ol></li><li class="chapter-item "><a href="../../posts/ctf/CTF.html"><strong aria-hidden="true">20.</strong> CTF</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ctf/CTF_Note.html"><strong aria-hidden="true">20.1.</strong> CTF Note</a></li><li class="chapter-item "><a href="../../posts/ctf/0.1_Web.html"><strong aria-hidden="true">20.2.</strong> Web</a></li><li class="chapter-item "><a href="../../posts/ctf/4.1_Misc.html"><strong aria-hidden="true">20.3.</strong> Misc</a></li><li class="chapter-item "><a href="../../posts/ctf/3.2_PWN_note.html"><strong aria-hidden="true">20.4.</strong> PWN</a></li><li class="chapter-item "><a href="../../posts/ctf/3.1_Crypto.html"><strong aria-hidden="true">20.5.</strong> Crypto</a></li><li class="chapter-item "><a href="../../posts/ctf/3.4_RSA_note.html"><strong aria-hidden="true">20.6.</strong> Rsa attack</a></li><li class="chapter-item "><a href="../../posts/ctf/3.5_Base64.html"><strong aria-hidden="true">20.7.</strong> Base64</a></li><li class="chapter-item "><a href="../../posts/ctf/0.0_SQL Injection Cheatsheet.html"><strong aria-hidden="true">20.8.</strong> SQL Injection Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/ctf/1.1_SQL_injection.html"><strong aria-hidden="true">20.9.</strong> SQL Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.2_SQL_injection_UNION_attacks.html"><strong aria-hidden="true">20.10.</strong> SQL Injection UNION attacks</a></li><li class="chapter-item "><a href="../../posts/ctf/1.3_Blind SQL injection.html"><strong aria-hidden="true">20.11.</strong> Blind SQL Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.4_Code Injection.html"><strong aria-hidden="true">20.12.</strong> Code Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.5_SSRF.html"><strong aria-hidden="true">20.13.</strong> SSRF</a></li><li class="chapter-item "><a href="../../posts/ctf/1.6_OS command injection.html"><strong aria-hidden="true">20.14.</strong> OS command injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.7_Local file inclusion.html"><strong aria-hidden="true">20.15.</strong> Local file inclusion</a></li><li class="chapter-item "><a href="../../posts/ctf/1.8_Remote file inclusion.html"><strong aria-hidden="true">20.16.</strong> Remote file inclusion</a></li><li class="chapter-item "><a href="../../posts/ctf/1.9_CSRFm.html"><strong aria-hidden="true">20.17.</strong> CSRF</a></li><li class="chapter-item "><a href="../../posts/ctf/1.10_NoSQL injection.html"><strong aria-hidden="true">20.18.</strong> NoSQL injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.11_JSON injection.html"><strong aria-hidden="true">20.19.</strong> JSON injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.12_CTF_Web_SQL_Note.html"><strong aria-hidden="true">20.20.</strong> CTF Web SQL Note</a></li><li class="chapter-item "><a href="../../posts/ctf/2.1_XXE.html"><strong aria-hidden="true">20.21.</strong> XXE</a></li><li class="chapter-item "><a href="../../posts/ctf/2.2_XSS.html"><strong aria-hidden="true">20.22.</strong> XSS</a></li><li class="chapter-item "><a href="../../posts/ctf/2.3_Upload File.html"><strong aria-hidden="true">20.23.</strong> Upload File</a></li><li class="chapter-item "><a href="../../posts/ctf/2.4_serialize_unserialize.html"><strong aria-hidden="true">20.24.</strong> serialize unserialize</a></li><li class="chapter-item "><a href="../../posts/ctf/2.5_Race condition.html"><strong aria-hidden="true">20.25.</strong> Race condition</a></li><li class="chapter-item "><a href="../../posts/ctf/zip_plain_text_attack.html"><strong aria-hidden="true">20.26.</strong> Zip plain text attack</a></li><li class="chapter-item "><a href="../../posts/ctf/3.3_pwn HCTF2016 brop.html"><strong aria-hidden="true">20.27.</strong> pwn HCTF2016 brop</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_patch_defense_skill.html"><strong aria-hidden="true">20.28.</strong> PWN Patch defense skill</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_stack_overflow.html"><strong aria-hidden="true">20.29.</strong> PWN stack overflow</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_heap_overflow.html"><strong aria-hidden="true">20.30.</strong> PWN heap overflow</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_format_string_vulnerability.html"><strong aria-hidden="true">20.31.</strong> PWN Format String Vulnerability</a></li><li class="chapter-item "><a href="../../posts/ctf/kali_linux_tutorials.html"><strong aria-hidden="true">20.32.</strong> Kali linux tutorials</a></li><li class="chapter-item "><a href="../../posts/ctf/google_dorks_2023_lists.html"><strong aria-hidden="true">20.33.</strong> Google Dorks 2023 Lists</a></li><li class="chapter-item "><a href="../../posts/ctf/dvwa_writeup.html"><strong aria-hidden="true">20.34.</strong> DVWA WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/bwapp_writeup.html"><strong aria-hidden="true">20.35.</strong> bWAPP WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/sqlilabs_writeup.html"><strong aria-hidden="true">20.36.</strong> sqlilabs WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/pwnable_kr_challenge.html"><strong aria-hidden="true">20.37.</strong> Solutions for pwnable.kr</a></li><li class="chapter-item "><a href="../../posts/ctf/the_periodic_table.html"><strong aria-hidden="true">20.38.</strong> The Periodic Table</a></li><li class="chapter-item "><a href="../../posts/ctf/pwntools_cheatsheet.html"><strong aria-hidden="true">20.39.</strong> Pwntools Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/ctf/gdb_cheatsheet.html"><strong aria-hidden="true">20.40.</strong> GDB Cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/iltes/iltes.html"><strong aria-hidden="true">21.</strong> ILTES</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/iltes/iltes_writing.html"><strong aria-hidden="true">21.1.</strong> ILTES Writing</a></li></ol></li></ol>
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                        <h1 id="es2015-cheatsheet"><a class="header" href="#es2015-cheatsheet">ES2015+ <em>cheatsheet</em></a></h1>
<p>A quick overview of new JavaScript features in ES2015, ES2016, ES2017, ES2018 and beyond.</p>
<h3 id="block-scoping"><a class="header" href="#block-scoping">Block scoping</a></h3>
<h4 id="let"><a class="header" href="#let">Let</a></h4>
<pre><code>function fn () {
  let x = 0
  if (true) {
    let x = 1 // only inside this `if`
  }
}

 

 
</code></pre>
<h4 id="const"><a class="header" href="#const">Const</a></h4>
<pre><code>const a = 1
</code></pre>
<p><code>let</code> is the new <code>var</code>. Constants work just like <code>let</code>, but can’t be reassigned. See: <a href="https://babeljs.io/learn-es2015/#let--const">Let and const</a></p>
<h3 id="backtick-strings"><a class="header" href="#backtick-strings">Backtick strings</a></h3>
<h4 id="interpolation"><a class="header" href="#interpolation">Interpolation</a></h4>
<pre><code>const message = `Hello ${name}`
</code></pre>
<h4 id="multiline-strings"><a class="header" href="#multiline-strings">Multiline strings</a></h4>
<pre><code>const str = `
hello
world
`
</code></pre>
<p>Templates and multiline strings. See: <a href="https://babeljs.io/learn-es2015/#template-strings">Template strings</a></p>
<h3 id="binary-and-octal-literals"><a class="header" href="#binary-and-octal-literals">Binary and octal literals</a></h3>
<pre><code>let bin = 0b1010010
let oct = 0o755
</code></pre>
<p>See: <a href="https://babeljs.io/learn-es2015/#binary-and-octal-literals">Binary and octal literals</a></p>
<h3 id="new-methods"><a class="header" href="#new-methods">New methods</a></h3>
<h4 id="new-string-methods"><a class="header" href="#new-string-methods">New string methods</a></h4>
<pre><code>&quot;hello&quot;.repeat(3)
&quot;hello&quot;.includes(&quot;ll&quot;)
&quot;hello&quot;.startsWith(&quot;he&quot;)
&quot;hello&quot;.padStart(8) // &quot;   hello&quot;
&quot;hello&quot;.padEnd(8) // &quot;hello   &quot; 
&quot;hello&quot;.padEnd(8, '!') // hello!!!
&quot;\u1E9B\u0323&quot;.normalize(&quot;NFC&quot;)
</code></pre>
<p>See: <a href="https://babeljs.io/learn-es2015/#math--number--string--object-apis">New methods</a></p>
<h3 id="classes"><a class="header" href="#classes">Classes</a></h3>
<pre><code>class Circle extends Shape {
</code></pre>
<h4 id="constructor"><a class="header" href="#constructor">Constructor</a></h4>
<pre><code>  constructor (radius) {
    this.radius = radius
  }

 
</code></pre>
<h4 id="methods"><a class="header" href="#methods">Methods</a></h4>
<pre><code>  getArea () {
    return Math.PI * 2 * this.radius
  }

 
</code></pre>
<h4 id="calling-superclass-methods"><a class="header" href="#calling-superclass-methods">Calling superclass methods</a></h4>
<pre><code>  expand (n) {
    return super.expand(n) * Math.PI
  }

 
</code></pre>
<h4 id="static-methods"><a class="header" href="#static-methods">Static methods</a></h4>
<pre><code>  static createFromDiameter(diameter) {
    return new Circle(diameter / 2)
  }
}

 
</code></pre>
<p>Syntactic sugar for prototypes. See: <a href="https://babeljs.io/learn-es2015/#classes">Classes</a></p>
<h3 id="exponent-operator"><a class="header" href="#exponent-operator">Exponent operator</a></h3>
<pre><code>const byte = 2 ** 8
// Same as: Math.pow(2, 8)

 
</code></pre>
<h2 id="promises"><a class="header" href="#promises">Promises</a></h2>
<h3 id="making-promises"><a class="header" href="#making-promises">Making promises</a></h3>
<pre><code>new Promise((resolve, reject) =&gt; {
  if (ok) { resolve(result) }
  else { reject(error) }
})

 
</code></pre>
<p>For asynchronous programming. See: <a href="https://babeljs.io/learn-es2015/#promises">Promises</a></p>
<h3 id="using-promises"><a class="header" href="#using-promises">Using promises</a></h3>
<pre><code>promise
  .then((result) =&gt; { ··· })
  .catch((error) =&gt; { ··· })

 

 
</code></pre>
<h3 id="using-promises-with-finally"><a class="header" href="#using-promises-with-finally">Using promises with finally</a></h3>
<pre><code>promise
  .then((result) =&gt; { ··· })
  .catch((error) =&gt; { ··· })
  .finally(() =&gt; { // logic independent of success/error })

 
</code></pre>
<p>The handler is called when the promise is fulfilled or rejected.</p>
<h3 id="promise-functions"><a class="header" href="#promise-functions">Promise functions</a></h3>
<pre><code>Promise.all(···)
Promise.race(···)
Promise.reject(···)
Promise.resolve(···)
</code></pre>
<h3 id="async-await"><a class="header" href="#async-await">Async-await</a></h3>
<pre><code>async function run () {
  const user = await getUser()
  const tweets = await getTweets(user)
  return [user, tweets]
}

 

 
</code></pre>
<p><code>async</code> functions are another way of using functions.</p>
<p>See: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/async_function">async function</a></p>
<h2 id="destructuring"><a class="header" href="#destructuring">Destructuring</a></h2>
<h3 id="destructuring-assignment"><a class="header" href="#destructuring-assignment">Destructuring assignment</a></h3>
<h4 id="arrays"><a class="header" href="#arrays">Arrays</a></h4>
<pre><code>const [first, last] = ['Nikola', 'Tesla']

 
</code></pre>
<h4 id="objects"><a class="header" href="#objects">Objects</a></h4>
<pre><code>let {title, author} = {
  title: 'The Silkworm',
  author: 'R. Galbraith'
}

 
</code></pre>
<p>Supports for matching arrays and objects. See: <a href="https://babeljs.io/learn-es2015/#destructuring">Destructuring</a></p>
<h3 id="default-values"><a class="header" href="#default-values">Default values</a></h3>
<pre><code>const scores = [22, 33]
const [math = 50, sci = 50, arts = 50] = scores
</code></pre>
<pre><code>// Result:
// math === 22, sci === 33, arts === 50
</code></pre>
<p>Default values can be assigned while destructuring arrays or objects.</p>
<h3 id="function-arguments"><a class="header" href="#function-arguments">Function arguments</a></h3>
<pre><code>function greet({ name, greeting }) {
  console.log(`${greeting}, ${name}!`)
}

 
</code></pre>
<pre><code>greet({ name: 'Larry', greeting: 'Ahoy' })
</code></pre>
<p>Destructuring of objects and arrays can also be done in function arguments.</p>
<h3 id="default-values-1"><a class="header" href="#default-values-1">Default values</a></h3>
<pre><code>function greet({ name = 'Rauno' } = {}) {
  console.log(`Hi ${name}!`);
}

 
</code></pre>
<pre><code>greet() // Hi Rauno!
greet({ name: 'Larry' }) // Hi Larry!
</code></pre>
<h3 id="reassigning-keys"><a class="header" href="#reassigning-keys">Reassigning keys</a></h3>
<pre><code>function printCoordinates({ left: x, top: y }) {
  console.log(`x: ${x}, y: ${y}`)
}

 
</code></pre>
<pre><code>printCoordinates({ left: 25, top: 90 })
</code></pre>
<p>This example assigns <code>x</code> to the value of the <code>left</code> key.</p>
<h3 id="loops"><a class="header" href="#loops">Loops</a></h3>
<pre><code>for (let {title, artist} of songs) {
  ···
}

 
</code></pre>
<p>The assignment expressions work in loops, too.</p>
<h3 id="object-destructuring"><a class="header" href="#object-destructuring">Object destructuring</a></h3>
<pre><code>const { id, ...detail } = song;

 
</code></pre>
<p>Extract some keys individually and remaining keys in the object using rest (…) operator</p>
<h2 id="spread"><a class="header" href="#spread">Spread</a></h2>
<h3 id="object-spread"><a class="header" href="#object-spread">Object spread</a></h3>
<h4 id="with-object-spread"><a class="header" href="#with-object-spread">with Object spread</a></h4>
<pre><code>const options = {
  ...defaults,
  visible: true
}

 
</code></pre>
<h4 id="without-object-spread"><a class="header" href="#without-object-spread">without Object spread</a></h4>
<pre><code>const options = Object.assign(
  {}, defaults,
  { visible: true })
</code></pre>
<p>The Object spread operator lets you build new objects from other objects.</p>
<p>See: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_operator">Object spread</a></p>
<h3 id="array-spread"><a class="header" href="#array-spread">Array spread</a></h3>
<h4 id="with-array-spread"><a class="header" href="#with-array-spread">with Array spread</a></h4>
<pre><code>const users = [
  ...admins,
  ...editors,
  'rstacruz'
]

 

 
</code></pre>
<h4 id="without-array-spread"><a class="header" href="#without-array-spread">without Array spread</a></h4>
<pre><code>const users = admins
  .concat(editors)
  .concat([ 'rstacruz' ])
</code></pre>
<p>The spread operator lets you build new arrays in the same way.</p>
<p>See: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_operator">Spread operator</a></p>
<h2 id="functions"><a class="header" href="#functions">Functions</a></h2>
<h3 id="function-arguments-1"><a class="header" href="#function-arguments-1">Function arguments</a></h3>
<h4 id="default-arguments"><a class="header" href="#default-arguments">Default arguments</a></h4>
<pre><code>function greet (name = 'Jerry') {
  return `Hello ${name}`
}

 
</code></pre>
<h4 id="rest-arguments"><a class="header" href="#rest-arguments">Rest arguments</a></h4>
<pre><code>function fn(x, ...y) {
  // y is an Array
  return x * y.length
}

 
</code></pre>
<h4 id="spread-1"><a class="header" href="#spread-1">Spread</a></h4>
<pre><code>fn(...[1, 2, 3])
// same as fn(1, 2, 3)

 
</code></pre>
<p>Default, rest, spread. See: <a href="https://babeljs.io/learn-es2015/#default--rest--spread">Function arguments</a></p>
<h3 id="fat-arrows"><a class="header" href="#fat-arrows">Fat arrows</a></h3>
<h4 id="fat-arrows-1"><a class="header" href="#fat-arrows-1">Fat arrows</a></h4>
<pre><code>setTimeout(() =&gt; {
  ···
})

 
</code></pre>
<h4 id="with-arguments"><a class="header" href="#with-arguments">With arguments</a></h4>
<pre><code>readFile('text.txt', (err, data) =&gt; {
  ...
})

 
</code></pre>
<h4 id="implicit-return"><a class="header" href="#implicit-return">Implicit return</a></h4>
<pre><code>numbers.map(n =&gt; n * 2)
// No curly braces = implicit return
// Same as: numbers.map(function (n) { return n * 2 })
numbers.map(n =&gt; ({
  result: n * 2
}))
// Implicitly returning objects requires parentheses around the object

 
</code></pre>
<p>Like functions but with <code>this</code> preserved. See: <a href="https://babeljs.io/learn-es2015/#arrows-and-lexical-this">Fat arrows</a></p>
<h2 id="objects-1"><a class="header" href="#objects-1">Objects</a></h2>
<h3 id="shorthand-syntax"><a class="header" href="#shorthand-syntax">Shorthand syntax</a></h3>
<pre><code>module.exports = { hello, bye }
// Same as: module.exports = { hello: hello, bye: bye }
</code></pre>
<p>See: <a href="https://babeljs.io/learn-es2015/#enhanced-object-literals">Object literal enhancements</a></p>
<h3 id="methods-1"><a class="header" href="#methods-1">Methods</a></h3>
<pre><code>const App = {
  start () {
    console.log('running')
  }
}
// Same as: App = { start: function () {···} }

 
</code></pre>
<p>See: <a href="https://babeljs.io/learn-es2015/#enhanced-object-literals">Object literal enhancements</a></p>
<h3 id="getters-and-setters"><a class="header" href="#getters-and-setters">Getters and setters</a></h3>
<pre><code>const App = {
  get closed () {
    return this.status === 'closed'
  },
  set closed (value) {
    this.status = value ? 'closed' : 'open'
  }
}

 

 
</code></pre>
<p>See: <a href="https://babeljs.io/learn-es2015/#enhanced-object-literals">Object literal enhancements</a></p>
<h3 id="computed-property-names"><a class="header" href="#computed-property-names">Computed property names</a></h3>
<pre><code>let event = 'click'
let handlers = {
  [`on${event}`]: true
}
// Same as: handlers = { 'onclick': true }

 
</code></pre>
<p>See: <a href="https://babeljs.io/learn-es2015/#enhanced-object-literals">Object literal enhancements</a></p>
<h3 id="extract-values"><a class="header" href="#extract-values">Extract values</a></h3>
<pre><code>const fatherJS = { age: 57, name: &quot;Brendan Eich&quot; }

Object.values(fatherJS)
// [57, &quot;Brendan Eich&quot;]
Object.entries(fatherJS)
// [[&quot;age&quot;, 57], [&quot;name&quot;, &quot;Brendan Eich&quot;]]

 

 
</code></pre>
<h2 id="modules"><a class="header" href="#modules">Modules</a></h2>
<h3 id="imports"><a class="header" href="#imports">Imports</a></h3>
<pre><code>import 'helpers'
// aka: require('···')
</code></pre>
<pre><code>import Express from 'express'
// aka: const Express = require('···').default || require('···')
</code></pre>
<pre><code>import { indent } from 'helpers'
// aka: const indent = require('···').indent
</code></pre>
<pre><code>import * as Helpers from 'helpers'
// aka: const Helpers = require('···')
</code></pre>
<pre><code>import { indentSpaces as indent } from 'helpers'
// aka: const indent = require('···').indentSpaces
</code></pre>
<p><code>import</code> is the new <code>require()</code>. See: <a href="https://babeljs.io/learn-es2015/#modules">Module imports</a></p>
<h3 id="exports"><a class="header" href="#exports">Exports</a></h3>
<pre><code>export default function () { ··· }
// aka: module.exports.default = ···
</code></pre>
<pre><code>export function mymethod () { ··· }
// aka: module.exports.mymethod = ···
</code></pre>
<pre><code>export const pi = 3.14159
// aka: module.exports.pi = ···
</code></pre>
<p><code>export</code> is the new <code>module.exports</code>. See: <a href="https://babeljs.io/learn-es2015/#modules">Module exports</a></p>
<h2 id="generators"><a class="header" href="#generators">Generators</a></h2>
<h3 id="generators-1"><a class="header" href="#generators-1">Generators</a></h3>
<pre><code>function* idMaker () {
  let id = 0
  while (true) { yield id++ }
}
</code></pre>
<pre><code>let gen = idMaker()
gen.next().value  // → 0
gen.next().value  // → 1
gen.next().value  // → 2
</code></pre>
<p>It’s complicated. See: <a href="https://babeljs.io/learn-es2015/#generators">Generators</a></p>
<h3 id="forof-iteration"><a class="header" href="#forof-iteration">For..of iteration</a></h3>
<pre><code>for (let i of iterable) {
  ···
}
</code></pre>
<p>For iterating through generators and arrays. See: <a href="https://babeljs.io/learn-es2015/#iterators--forof">For..of iteration</a></p>

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